Prognostic significance of thymidylate synthase expression in pancreatic adenocarcinoma: A meta-analysis

The prognostic significance of thymidylate synthase (TS) overexpression in pancreatic adenocarcinoma has been extensively investigated; however, data on the survival of patients with pancreatic adenocarcinoma remain equivocal. We performed a meta-analysis of previous studies to assess the effects of TS overexpression on the overall survival (OS) of patients with pancreatic adenocarcinoma, using hazard ratio (HR) with its 95% confidence interval (CI). A total of 5 studies, including 425 patients, were subjected to the final analysis. The pooled HR was 0.72 (95% CI: 0.41-1.25; Z=1.18, P=0.238), indicating that TS expression exerted no significant survival effect on patients with pancreatic adenocarcinoma. The combined HR was 0.46 (95% CI: 0.31-0.68; Z=3.95, P<0.001), limiting the analysis to the studies assessing R0 resection patients, which indicated that a high expression of TS was significantly correlated with better OS in patients with pancreatic adenocarcinoma who underwent R0 resection. This meta-analysis identified TS as an independent factor predicting favourable outcome following R0 curative resection in patients with pancreatic adenocarcinoma.